Why isn't my environment variable working?

The problem

You added the variable. The feature still behaves as though it is missing — an unauthenticated request, a blank configuration, or a thrown error naming the variable.

What it means

The running process does not have that value. Not that you did not save it — that this process, in this environment, at this moment, cannot see it.

Common causes

How to diagnose it

1. 1Log whether the value is present — its length, never the value itself.
2. 2Log the environment name alongside it so you know where the code is running.
3. 3Compare the variable list in your hosting configuration against the names in your code, character by character.
4. 4For browser values, check the built output actually contains the substituted value.
5. 5Redeploy and check again before changing any code.

console.log("PROVIDER_KEY present:", Boolean(process.env.PROVIDER_KEY));
// never log the value itself

How to fix it

• Set the variable in every environment that needs it, then redeploy.
• Make the name identical everywhere, including case.
• Move the read inside the function that uses it.
• Add the required prefix only for values that are genuinely public.
• Throw an explicit error when it is missing, so the next failure names itself.

What AI may have done

• Read the variable at the top of a module, before the environment is injected.
• Chosen a plausible name that differs from the one you created.
• Defaulted to an empty string to avoid a crash, converting a clear failure into a confusing one.
• Added a public prefix to a secret so it would work in a component.

How to verify the fix

1. 1Redeploy and confirm the presence check logs true in the target environment.
2. 2Exercise the feature that depends on it, in that environment.
3. 3Confirm a browser-visible value is not a secret by searching the bundle for it.
4. 4Remove the temporary logging.

How to prevent it

• Keep a committed example file listing required names with empty values.
• Validate required variables at start-up and fail loudly.
• Never default a credential to an empty string.
• Keep the same names across environments so only values differ.